Engineering Commons^™

Sustainability Of Utilizing Renewable And Nuclear Energy In Saudi Arabia Using Different Types Of Life Cycle Assessment, Kamel Almutairi

Graduate Theses and Dissertations

Evaluating the global environmental impacts of the current and future energy policies in Saudi Arabia using Life cycle assessment (LCA) method was the main objective of this dissertation. First, the attributional life cycle assessment (ALCA) framework was used to evaluate the Saudi’s air conditioning systems, as they are responsible for about 70% of the total Saudi residential electricity consumption. The ALCA’s results showed that the AC use phase produces the largest share of the environmental impact and the magnitude of the environmental impacts is influenced by the type of primary fuel used for electricity generation.

Emerging non-fossil sources of electricity …

Efficacy Of Multi-Threshold Null Convention Logic In Low-Power Applications, Brent Bell

Graduate Theses and Dissertations

In order for an asynchronous design paradigm such as Multi-Threshold NULL Convention Logic (MTNCL) to be adopted by industry, it is important for circuit designers to be aware of its advantages and drawbacks especially with respect to power usage. The power tradeoff between MTNCL and synchronous designs depends on many different factors including design type, circuit size, process node, and pipeline granularity. Each of these design dimensions influences the active power and the leakage power comparisons. This dissertation analyzes the effects of different design dimensions on power consumption and the associated rational for these effects. Results show that while MTNCL …

Evaluation Of A Solar Powered Variable Flow Tail Water Recovery System For Furrow Irrigation, Vaishali Kandpal

Graduate Theses and Dissertations

Furrow irrigation is a very common irrigation method for growing crops like soybean, cotton and corn in Arkansas. A major portion of this irrigation water is lost as runoff from the field significantly reducing the irrigation application efficiency. There are various methods of improving irrigation efficiency and one of the methods is using tail-water recovery. A tail-water recovery system utilizes tail-water recovery ditches or pits to collect tail-water which can be re-used for irrigation. However, this method is very labor intensive and has been found to be economically non-feasible for some farms in the past research studies. In order to …

Incorporation Of Silica Nanoparticles Into The Underlayer Of Pda/Ptfe Thin Coatings, Adedoyin Abe

Mechanical Engineering Undergraduate Honors Theses

Polytetrafluoroethylene (PTFE) is one of the most low friction and corrosion resistant solid lubricants. Prior studies have shown that a polydopamine (PDA) underlayer enhances the durability of PTFE thin coating. In this study, 100, 200, and 300 µL of aqueous silica nanoparticle (NP) solutions were added to the PDA deposition solution. The durability and coefficient of friction of PDA/PTFE thin coatings on stainless steel substrates are investigated with and without incorporating the silica NPs. The coatings were tested in dry contact conditions using a Universal Mechanical Tester (UMT) with a ball-on-flat configuration in a reciprocating motion. It was found that …

Gold Nanoparticles For Stem Cell Delivery In Myocardial Infarction: Analysis Of Toxicity And Development Of A Cell Culture Platform For Use In An In-Vitro Model Of Mi-Associated Ischemia/Reperfusion, Jeffrey Curran Henson

Graduate Theses and Dissertations

In this work, the potential for PEGylated gold nanoparticles for use as a platform for stem cell delivery in treatment of myocardial infarction (MI) is preliminarily investigated. Cardiovascular disease is currently the leading cause of death worldwide, with majority of mortality resulting from coronary artery disease and associated MI. The ensuing ischemic conditions resulting from MI cause substantial heart muscle tissue loss and scarring in the heart. Adverse tissue remodeling creates a significant loss in heart function that can result in the formation of cardiac hypertrophy, ventricular dilation and arrythmias. The long-term prognosis of patients who have suffered MI is …

Membrane-Based Separation Processes For Treating High Salinity Produced Waters, Kamyar Sardari

Graduate Theses and Dissertations

Produced waters (PW) generated in the oil and gas industry within the United States often contain extreme levels of total dissolved solids (TDS). These high TDS waste streams need to be treated cost-effectively as the costs associated with the current management techniques can exceed 15 USD per barrel of discharged PW. Thermally and osmotically-driven membrane separation technologies can show promising potential for treating high TDS waste streams, as onsite low-grade waste heat may be used for their operation. In this dissertation, the application of membrane distillation (MD), forward osmosis (FO) and a hybrid FO-MD process for treating synthetic and actual …

Configuring Traditional Multi-Dock, Unit-Load Warehouses, Mahmut Tutam

Graduate Theses and Dissertations

The development of expected-distance formulas for multi-dock-door, unit-load warehouse configurations is the focus of the dissertation. From formulations derived, the width-to-depth ratios minimizing expected distances are obtained for rectangle-shaped, unit-load warehouse configurations. Partitioning the storage region in the warehouse into three classes, the performance of a multi-dock-door, unit-load warehouse is studied when storage regions can be either rectangle-shaped or contour-line-shaped. Our first contribution is the development of formulas for expected distance traveled in storing and retrieving unit loads in a rectangle-shaped warehouse having multiple dock doors along one warehouse wall and storage racks aligned perpendicular to that wall. Two formulations …

Modeling And Solution Approaches For Non-Traditional Network Flow Problems With Complicating Constraints, Negin Enayaty Ahangar

Graduate Theses and Dissertations

In this dissertation, we model three network-based optimization problems. Chapter 2 addresses the question of what the operation plan should be for interdependent infrastructure systems in resource-constrained environments so that they collectively operate at the highest level. We develop a network-based operation model of these systems that accounts for interdependencies among them. To solve this large-scale model, a solution approach is proposed that relatively quickly generates high-quality solutions to the problem.

Chapter 3 presents a routing model for a single train within a railyard with the objective of minimizing the total length traveled by train. The difference between this problem …

Barge Prioritization, Assignment, And Scheduling During Inland Waterway Disruption Responses, Liliana Delgado-Hidalgo

Graduate Theses and Dissertations

Inland waterways face natural and man-made disruptions that may affect navigation and infrastructure operations leading to barge traffic disruptions and economic losses. This dissertation investigates inland waterway disruption responses to intelligently redirect disrupted barges to inland terminals and prioritize offloading while minimizing total cargo value loss. This problem is known in the literature as the cargo prioritization and terminal allocation problem (CPTAP). A previous study formulated the CPTAP as a non-linear integer programming (NLIP) model solved with a genetic algorithm (GA) approach. This dissertation contributes three new and improved approaches to solve the CPTAP.

The first approach is a decomposition …

High-Sn-Content Gesn Alloy Towards Room-Temperature Mid Infrared Laser, Wei Dou

Graduate Theses and Dissertations

Si photonics is a rapidly expanding technology that integrates photonic circuits onto a Si substrate. The integration of Si electronics and photonics has been a successful technology for a wide range of applications. Group-IV alloy GeSn has drawn great attentions as a complementary metal–oxide–semiconductor compatible optoelectronic material for Si photonics. The devices based on GeSn alloy could be monolithically integrated into well-established and high-yield Si integrated circuits, which is favorable for chip-scale Si photonics featuring smaller size, lower cost, and higher reliability.

The relaxed GeSn with high material quality and high Sn composition is highly desirable to cover mid-infrared wavelength. …

Opto-Thermal Characterization Of Plasmon And Coupled Lattice Resonances In 2-D Metamaterial Arrays, Vinith Bejugam

Graduate Theses and Dissertations

Growing population and climate change inevitably requires longstanding dependency on sustainable sources of energy that are conducive to ecological balance, economies of scale and reduction of waste heat. Plasmonic-photonic systems are at the forefront of offering a promising path towards efficient light harvesting for enhanced optoelectronics, sensing, and chemical separations. Two-dimensional (2-D) metamaterial arrays of plasmonic nanoparticles arranged in polymer lattices developed herein support thermoplasmonic heating at off-resonances (near infrared, NIR) in addition to regular plasmonic resonances (visible), which extends their applicability compared to random dispersions. Especially, thermal responses of 2-D arrays at coupled lattice resonance (CLR) wavelengths were comparable …

Determining The Effect Of Locally Delivered Bioactive Modulators On Macrophage Activation At The Implantation Site Of Different Biomaterials In Rats, Kamel Alkhatib

Graduate Theses and Dissertations

Altering the foreign body reaction by targeting macrophages has been of interest in the biomaterials field to improve the integration of longevity of implanted biomedical devices. The objective of this dissertation was to study the effect of locally delivered bioactive modulators on macrophage activation at the implantation site of different biomaterials in rats. Iloprost, a prostacyclin analog, was tested for its ability to direct macrophages to their pro-wound healing phenotype after the implantation of microdialysis probe in the subcutaneous space of male Sprague Dawley rats. This study showed that iloprost can shift macrophage activation states in vivo to the pro-wound …

Design Of Peptoid-Based Coating To Reduce Biofouling In Gas Exchange Devices, Neda Mahmoudi

Graduate Theses and Dissertations

In recent decades, membrane technology has been used commonly in biomedical area. However, membrane fouling is a widespread problem in different applications. One method to minimize fouling is through surface modification of membranes. My research explores a novel polymer to minimize nonspecific protein adsorption in biomedical applications.

It firstly focuses on grafting the electrically neutral NMEG peptoid, containing 2-methoxyethyl side chains, to polysulfone (PSU) membrane via polydopamine. Contact angle measurements indicated that the hydrophilicity of the peptoid-grafted membranes was significantly improved while the pore size and strength of the membranes remained unchanged. The modified membranes showed an improved fouling resistance …

Si-Based Germanium Tin Photodetectors For Short-Wave And Mid-Wave Infrared Detections, Thach Pham

Graduate Theses and Dissertations

The demand of light-weight and inexpensive imaging system working in the infrared range keeps increasing for the last decade, especially for civil applications. Although several group IV materials such as silicon and germanium are used to realize detectors in the visible and near infrared region, they are not the efficient approach for imaging system in the short-wave infrared detection range and beyond due to bandgap limit. On the other hand, this market is heavily relied upon mature technology from III-V and II-VI elements over years, which are costly to growth and incompatible with available Si complementary metal-oxide-semiconductor (CMOS) foundries. This …

Properties Of Matter, Mike Jackson, Holly Haney

High School Lesson Plans

Students will investigate the relationship(s) between thermal and electrical properties of matter. First, students will use a multimeter and temperature probe to investigate the relationship between electrical resistance and temperature of an electrical resistor composed of metals. They will then graph collected data to analyze the relationship and draw a conclusion as to their relationship. They will then perform the same investigation on a thermal resistor made of a semiconducting substance and analyze that collected data. Finally, using ClaimEvidence-Reasoning (CER) structure, students will use their experimental evidence to state the similarities and differences between the electro-thermal properties of metals and …

What Can I Do As A Student To Make A Positive Impact On The Environment?, Tammy Guthrie, Greg Herzig, Kathy Prophet, Cassie Kautzer

Middle School Lesson Plans

Students discover ways they can make a positive impact on the environment.

Designing A Distributed Network Of Air Quality Sensors, Kaylee Rauso

Computer Science and Computer Engineering Undergraduate Honors Theses

The deterioration of human and environmental health due to worsening outdoor air quality is a serious global threat. A step towards improving the current state of ambient air worldwide is the increased collection of data for government policy, research, and general public use. Currently, reliable data is only collected at a handful of sites in the state of Arkansas and sparsely across the country. The purpose of this project was to design an inexpensive air quality sensor to saturate entire cities with nodes which transmit air data to a sensor for a web application to display. The prototype node was …

A Folded Cascode Operational Amplifier With Wide-Swing Current Mirrors And High Icmr, Designed With A 1.2-Micron Silicon-Carbide Process, Austin Gattis

Electrical Engineering Undergraduate Honors Theses

This thesis describes in detail the process of designing, simulating, and creating the layout for a modified folded cascode op-amp, fabricated with silicon carbide MOSFETS. The modifications consist of using a wide-swing current mirror to help deal with output voltage issues stemming from high threshold voltages in the silicon carbide process, as well as using a modification that allows for an increased input common mode range. The folded cascode op-amp uses silicon carbide transistors, as it is intended to be used for high temperature applications, ideally in the 25 C - 300 C range. It is designed to have 25 …

Command Validation For Cybersecure Power Router, Isaac M. Kroger

Electrical Engineering Undergraduate Honors Theses

For grid-connected homes equipped with solar panels, power electronics are necessary to manage and convert power between the solar panels, battery storage, grid, and residential load. A power router can be used to manage these power electronics and govern power generation, storage, and distribution within the household. This level of control makes power routers that do not employ cybersecurity a target for external attacks. The use of command validation is an effective way to prevent unauthorized commands from maliciously altering the state of a home’s power router. The purpose of this thesis is to describe the development of the command …

Comparison Of Data Transfer Alternatives In Asynchronous Circuits, Mark Howard

Computer Science and Computer Engineering Undergraduate Honors Theses

Digital integrated circuits (ICs) have become progressively complex in their functionality. This has sped up the demand for asynchronous architectures, which operate without any clocking scheme, considering new challenges in the timing of synchronous systems. Asynchronous ICs have less stringent environmental constraints and are capable of maintaining reliable operation in extreme environments, while also enjoying potential benefits such as low power consumption, high modularity, and improved performance. However, when the traditional bus architecture of synchronous systems is applied to asynchronous designs, handshaking protocols required for asynchronous circuit operation result in significantly increased power consumption, offsetting the low power benefit of …

Comparison Of Google Image Search And Resnet Image Classification Using Image Similarity Metrics, David Smith

Computer Science and Computer Engineering Undergraduate Honors Theses

In this paper, we compare the results of ResNet image classification with the results of Google Image search. We created a collection of 1,000 images by performing ten Google Image searches with a variety of search terms. We classified each of these images using ResNet and inspected the results. The ResNet classifier predicted the category that matched the search term of the image 77.5% of the time. In our best case, with the search term “forklift”, the classifier categorized 92 of the 100 images as forklifts. In the worst case, for the category “hammer”, the classifier matched the search term …

Automatic Testing In The United States Air Force, Pearson Wade

Computer Science and Computer Engineering Undergraduate Honors Theses

The need for standardized Automatic Testing Equipment in the United States Department of Defense has brought about new policies and procedures within entities like the United States Air Force. The diversity and lifespan of systems such as jets, missiles, drones, and other electronics have brought on the need for a new system known as the Versatile Depot Automatic Test Station, or VDATS. The VDATS handles the automatic testing of replaceable digital circuits from different systems. I was introduced to this system firsthand during my time as an intern at Tinker AFB, Oklahoma. This new standardized approach to testing a diverse …

Scada And Plc Systems Configuration For The Ncrept Test Facility, Arman Ahmed

Electrical Engineering Undergraduate Honors Theses

This thesis details the project to update the control and interface system of the National Center for Reliable Electric Power Transmission (NCREPT) testing facility. The need for this project arose from the 2017-2018 expansion of the facility, which included some modifications in the layout of electrical equipment used for testing purposes. These modifications necessitated the update of the control and interface system. Additionally, the old system was implemented a decade ago and is nearing obsolescence, so the facility’s expansion served as an opportune time for an upgrade.

There were two main parts to the scope of this project, which were …

Dynamic 3d Network Data Visualization, Brok Stafford

Computer Science and Computer Engineering Undergraduate Honors Theses

Monitoring network traffic has always been an arduous and tedious task because of the complexity and sheer volume of network data that is being consistently generated. In addition, network growth and new technologies are rapidly increasing these levels of complexity and volume. An effective technique in understanding and managing a large dataset, such as network traffic, is data visualization. There are several tools that attempt to turn network traffic into visual stimuli. Many of these do so in 2D space and those that are 3D lack the ability to display network patterns effectively. Existing 3D network visualization tools lack user …

The 3d Abstract Tile Assembly Model Is Intrinsically Universal, Aaron Koch, Daniel Hader, Matthew J. Patitz

Computer Science and Computer Engineering Undergraduate Honors Theses

In this paper, we prove that the three-dimensional abstract Tile Assembly Model (3DaTAM) is intrinsically universal. This means that there is a universal tile set in the 3DaTAM which can be used to simulate any 3DaTAM system. This result adds to a body of work on the intrinsic universality of models of self-assembly, and is specifically motivated by a result in FOCS 2016 showing that any intrinsically universal tile set for the 2DaTAM requires nondeterminism (i.e. undirectedness) even when simulating directed systems. To prove our result we have not only designed, but also fully implemented what we believe to be …

An Embarrassment Of Riches: Data Integration In Vr Pompeii, Adam Schoelz

Computer Science and Computer Engineering Undergraduate Honors Theses

It is fair to say that Pompeii is the most studied archaeological site in the world. Beyond the extensive remains of the city itself, the timing of its rediscovery and excavation place it in a unique historiographical position. The city has been continuously studied since the 18th century, with historians and archaeologists constantly reevaluating older sources as our knowledge of the ancient world expands. While several studies have approached the city from a data driven perspective, no studies of the city have taken a quantitative holistic approach on the scale of the VR Pompeii project. Hyper-specificity has been the order …

Training Machine Learning Agents In A 3d Game Engine, Diego Calderon

Computer Science and Computer Engineering Undergraduate Honors Theses

Artificial intelligence (AI) and video games benefit from each other. Games provide a challenging domain for testing learning algorithms, and AI provides a framework to designing and implementing intelligent behavior, which reinforces meaningful play. Medium and small studios, and independent game developers, have limited resources to design, implement, and maintain agents with reactive behavior. In this research, we trained agents using machine learning (ML), aiming to find an alternative to expensive traditional algorithms for intelligent behavior used in video games. We use Unity as a game engine to implement the environments and TensorFlow for the neural network training.

High Temperature Wide Bandgap Light Emitting Diodes For Harsh Environment Applications, Stephanie Sandoval

Electrical Engineering Undergraduate Honors Theses

The need for high temperature, high power density power modules for applications such as electric vehicles and space exploration has driven the research into wide bandgap LEDs due to their potential operation at elevated temperatures. Wide bandgap LEDs offer an attractive solution due to properties such as high temperature tolerance, strong radiation hardness and good thermal conductivity. In this thesis, the electrical properties of GaN-on-SiC heterojunctions are studied as a precursor to an LED study, and the optical characterization of an InGaN/GaN MQW is reported. The GaN-on-SiC study revealed that these wide bandgap LEDs have linear sensitivity at high temperatures. …

Improving Spatial Visualization Abilities Using 3d Printed Blocks, Vanessa Lebow, Michelle Bernhardt-Barry, Jyotishka Datta

Civil Engineering Undergraduate Honors Theses

Spatial visualization abilities have been shown to be a key predictor of success in science, technology, engineering, and math fields. Past research has revealed that women and underrepresented minorities tend to lag behind in spatial visual abilities, however, research has also shown that these skills can be improved with guided practice. This study seeks to examine whether 3D printed aids help spatial visual retention in 6th graders. A modified Purdue spatial visualization test was used as the assessment standard. Students’ mental rotation abilities were assessed before and after the 3D printed aids were administered. Data was collected from five different …

A Numerical Investigation Of Bio-Inspired Scaffolds And Surface Textures, Yucong Gu

Graduate Theses and Dissertations

Synthetic scaffolds are widely used as implants to repair bone fracture. Without a proper design, scaffolds could pose significant health risks to the patient and fail to heal the bone properly. A good synthetic scaffold needs to have high porosity and large pore size to allow new bone cells to form on it. However, a scaffold with higher porosity and larger pore size tends to have reduced mechanical strength. Thus, it is important to find a structural design which allows the implant to have a high porosity and large pore size while retaining high strength. In this research, a 3D-printable …